U.S. patent application number 14/055894 was filed with the patent office on 2014-05-08 for sensor array and method of controlling sensing device and related electronic device.
This patent application is currently assigned to PixArt Imaging Inc.. The applicant listed for this patent is PixArt Imaging Inc.. Invention is credited to En-Feng Hsu.
Application Number | 20140124647 14/055894 |
Document ID | / |
Family ID | 50621479 |
Filed Date | 2014-05-08 |
United States Patent
Application |
20140124647 |
Kind Code |
A1 |
Hsu; En-Feng |
May 8, 2014 |
SENSOR ARRAY AND METHOD OF CONTROLLING SENSING DEVICE AND RELATED
ELECTRONIC DEVICE
Abstract
There is provided a method of reducing power consumption of a
gesture sensor. The method utilizes an auxiliary sensing device to
detect whether an object exists in a sensing covering range of the
gesture sensor, thereby determining operating states and power
consumptions of the gesture sensor and the auxiliary sensing
device. If the auxiliary sensing device does not detect that the
object exists in the sensing covering range of the gesture sensor
or the object moves, the gesture sensor is allowed to be in a low
power consumption operating state, thereby reducing the power
consumption.
Inventors: |
Hsu; En-Feng; (Hsin-Chu
City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PixArt Imaging Inc. |
Hsin-Chu City |
|
TW |
|
|
Assignee: |
PixArt Imaging Inc.
Hsin-Chu City
TW
|
Family ID: |
50621479 |
Appl. No.: |
14/055894 |
Filed: |
October 17, 2013 |
Current U.S.
Class: |
250/206.1 ;
250/208.2 |
Current CPC
Class: |
Y02D 10/171 20180101;
G06F 1/3262 20130101; G06F 1/3287 20130101; G06F 1/3231 20130101;
Y02D 10/00 20180101; Y02D 10/173 20180101; G06F 3/017 20130101;
G06F 3/0304 20130101 |
Class at
Publication: |
250/206.1 ;
250/208.2 |
International
Class: |
G06F 3/03 20060101
G06F003/03 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 6, 2012 |
TW |
101141137 |
Claims
1. An electronic device, comprising: a sensing system having a
first sensing device, for selectively detecting an object to
generate a first detection result, wherein the first detection
result indicates a state of motion of the object; a second sensing
device for selectively detecting the object to generate a second
detection result, wherein the second detection result indicates
whether the object is in a specific space; and a control unit,
coupled to the first sensing device and the second sensing device,
for controlling operating states of the first sensing device and
the second sensing device according to the first and the second
detection results.
2. The electronic device of claim 1, wherein when the first
detection result indicates the object leaves from the specific
space or the object is motionless, the control unit allows the
first sensing device to enter a low power consumption operating
state, and the first sensing device accordingly stops generating
the first detection result.
3. The electronic device of claim 1, wherein when the first
detection result indicates the object leaves from the specific
space or the object is motionless, the control unit allows the
second sensing device to enter a normal operating state, and the
second sensing device accordingly generates the second detection
result.
4. The electronic device of claim 1, wherein when the second
detection result indicates the object enters the specific space or
the object moves, the control unit allows the first sensing device
to enter a normal operating state, and the first sensing device
accordingly generates the first detection result.
5. The electronic device of claim 4, wherein before the control
unit allows the first sensing device to enter the normal operating
state, the first sensing device stops generating the first
detection result.
6. The electronic device of claim 1, wherein the sensing system
further comprises: a light emitting device, for illuminating the
object to make the first sensing device able to detect the state of
motion of the object, and the control unit turns on/off the light
emitting device according to the first and the second detection
results.
7. The electronic device of claim 1, wherein the first sensing
device and the second sensing device are portions of a sensor
array.
8. The electronic device of claim 1, wherein the first sensing
device and the second sensing device are disposed in a same
chip.
9. The electronic device of claim 1, wherein the second sensing
device is an ambient light sensor or a proximity sensor.
10. A sensor array, comprising: a plurality of first sensing units,
for selectively detecting an object to generate a first detection
result, wherein the first detection result indicates a state of
motion of the object; and at least one sensing unit, for
selectively detecting the object to generate a second detection
result, wherein the second detection result indicates whether the
object is in a specific space; wherein operating states of the
first sensing device and the second sensing device are determined
according to the first and the second detection results.
11. The sensor array of claim 10, wherein when the first detection
result indicates the object leaves from the specific space or the
object is motionless, the first sensing units enter a low power
consumption operating state and stop generating the first detection
result.
12. The sensor array of claim 10, wherein when the first detection
result indicates the object leaves from the specific space or the
object is motionless, the second sensing unit enters a normal
operating state and generates the second detection result.
13. The sensor array of claim 10, wherein when the second detection
result indicates the object enters the specific space or the object
moves, the first sensing units enter a normal operating state and
generates the first detection result.
14. The sensor array of claim 13, wherein before the first sensing
units enter the normal operating state, the first sensing units
stop generating the first detection result.
15. The sensor array of claim 10, wherein the second sensing unit
is at an edge of the sensor array.
16. A method of controlling sensing devices, comprising: utilizing
a first sensing device to selectively detect an object to generate
a first detection result, wherein the first detection result
indicates a state of motion of the object; utilizing a second
sensing device to selectively detect the object to generate a
second detection result, wherein the second detection result
indicates whether the object is in a specific space; and
controlling operating states of the first sensing device and the
second sensing device according to the first and the second
detection results.
17. The method of claim 16, wherein the step of controlling the
operating states of the first sensing device and the second sensing
device comprises: when the first detection result indicates the
object leaves from the specific space or the object is motionless,
allowing the first sensing device to enter a low power consumption
operating state and to stop generating the first detection
result.
18. The method of claim 16, wherein the step of controlling the
operating states of the first sensing device and the second sensing
device comprises: when the first detection result indicates the
object leaves from the specific space or the object is motionless,
allowing the second sensing device to enter a normal operating
state and to generate the second detection result.
19. The method of claim 16, wherein the step of controlling the
operating states of the first sensing device and the second sensing
device comprises: when the second detection result indicates the
object enters the specific space or the object moves, allowing the
first sensing device to enter a normal operating state and to
generate the first detection result.
20. The method of claim 16, wherein the step of controlling the
operating states of the first sensing device and the second sensing
device comprises: stopping generating the first detection result
before the first sensing device is allowed to enter the normal
operating state.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to video detection, and more
particularly, to a method that is able to reduce power consumption
of a gesture sensor, and a related electronic device and sensor
array.
[0003] 2. Description of the Prior Art
[0004] A sensing device of recognizing gesture (i.e., gesture
sensor) is widely used in a variety of applications, providing an
innovative and instinctive way of interacting human with machine,
which detects motion of a hand of a user and accordingly issues
control commands to a user interface. Generally, the sensing device
of recognizing the gesture includes components as shown in FIG. 1.
An active light source 110 periodically illuminates the hand and a
sensing device 120 periodically detects changes of lights and
shadows generated by illumination on the hand. Computation circuit
inside the sensing device 120 determines whether the motion of the
hand matches specific gesture patterns and accordingly generates
control commands. Operating frequencies of the active light source
110 and the sensing device 120 are illustrated in FIG. 2A. When the
hand leaves from a sensing covering range V of the sensing system
100, the active light source 110 and the sensing device 120 stop
periodically operating. Then, a standby mode is entered such that
power consumption can be saved. In the meantime, the active light
source temporarily stops illuminating the hand of the user. Also,
the sensing device 120 temporarily stops sampling changes of lights
and shadows. In order to re-activate the sensing system 100 when
the hands enter the sensing covering range again, the active light
source 110 and the sensing device 120 intermittently detect whether
the hand enter the sensing covering range V again (at a operating
frequency which is lower than a operating frequency of the normal
operating state). Once there is no change found between the lights
and the shadows, the sensing system 100 remains in the standby
mode. Otherwise, the sensing system 100 comes back to the normal
operating state, performing gesture recognition. Operating
frequencies regarding the active light source 110 and the sensing
device 120 is illustrated in FIG. 2B.
[0005] However, as the active light source 110 and the sensing
device 120 intermittently detects changes of the lights and the
shadows, re-activation of the sensing system 100 may be delayed if
the sensing device 120 cannot capture the motion of the hand
immediately (i.e., the hand moves too fast). This is because the
sensing system 100 is operated at a relatively low frequency under
the standby mode and may miss the motion of the hand. As a result,
the user feels delay when trying to re-activate the sensing system
from the standby mode.
SUMMARY OF THE INVENTION
[0006] With this in mind, it is one objective of the present
invention to provide detection and re-activation mechanism of a
gesture senor under a standby mode, which utilizes an auxiliary
sensing device to continually detects the hand instead of
intermittently activating the gesture sensor to detect the hand.
Therefore, the motion of the hand will not be missed and the
gesture sensor can enter the normal operating state once the user
tries to do so. Embodiments of the present invention provide a
variety of ways for implementing the auxiliary sensing device, all
of which cost less power than intermittently activating the gesture
sensor.
[0007] According to a first aspect of the present invention, an
electronic device is provided. The electronic device comprises: a
sensing system having a first sensing device, a second sensing
device and a control unit. The sensing system is arranged for
selectively detecting an object to generate a first detection
result, wherein the first detection result indicates a state of
motion of the object. The second sensing device is arranged for
selectively detecting the object to generate a second detection
result, wherein the second detection result indicates whether the
object is in a specific space. The control unit is coupled to the
first sensing device and the second sensing device, and is arranged
for controlling operating states of the first sensing device and
the second sensing device according to the first and the second
detection results.
[0008] According to a second aspect of the present invention, a
sensor array is provided. The sensor array comprises: a plurality
of first sensing units and at least second sensing unit. The first
sensing units is arranged for selectively detecting an object to
generate a first detection result, wherein the first detection
result indicates a state of motion of the object. The second
sensing unit is arranged for selectively detecting the object to
generate a second detection result, wherein the second detection
result indicates whether the object is in a specific space. In
addition, operating states of the first sensing device and the
second sensing device is determined according to the first and the
second detection results.
[0009] According to a third aspect of the present invention, a
method of controlling sensing devices is provided. The method
comprises: utilizing a first sensing device to selectively detect
an object to generate a first detection result, wherein the first
detection result indicates a state of motion of the object;
utilizing a second sensing device to selectively detect the object
to generate a second detection result, wherein the second detection
result indicates whether the object is in a specific space; and
controlling operating states of the first sensing device and the
second sensing device according to the first and the second
detection results.
[0010] These and other objectives of the present invention will no
doubt become obvious to those of ordinary skill in the art after
reading the following detailed description of the preferred
embodiment that is illustrated in the various figures and
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates a representation of a conventional
sensing system.
[0012] FIGS. 2A and 2B illustrate a diagram of operating
frequencies of components of the conventional sensing system in a
normal operating state and a standby mode.
[0013] FIG. 3 illustrates a representation of an electronic device
according to one embodiment of the present invention.
[0014] FIG. 4 illustrates a representation of a sensor array
according to one embodiment of the present invention.
[0015] FIG. 5 illustrates a diagram of operating frequencies of
components of the electronic device in a normal operating state and
a low power consumption operating state.
[0016] FIG. 6 illustrates a diagram of relationship between the
timing of a control command and power consumption level of
operating frequencies of components of the electronic device in a
normal operating state and a low power consumption operating state
components of the electronic device.
[0017] FIG. 7 illustrates a flow chart of a method of controlling
sensing devices according to one embodiment of the present
invention.
DETAILED DESCRIPTION
[0018] Certain terms are used throughout the following descriptions
and claims to refer to particular system components. As one skilled
in the art will appreciate, manufacturers may refer to a component
by different names. This document does not intend to distinguish
between components that differ in name but not differ in
functionality. In the following discussion and in the claims, the
terms "include", "including", "comprise", and "comprising" are used
in an open-ended fashion, and thus should be interpreted to mean
"including, but not limited to . . . " The terms "couple" and
"coupled" are intended to mean either an indirect or a direct
electrical connection. Thus, if a first device couples to a second
device, that connection may be through a direct electrical
connection, or through an indirect electrical connection via other
devices and connections.
[0019] Please refer to FIG. 3, which is a representation of an
electronic device according to one embodiment of the present
invention. As shown, an electronic device 300 comprises a sensing
system 310, a sensing device 320 and a control unit 330. The
sensing system 310 could be a gesture sensor, which further
includes a sensing device 315. The sensing device 315 is arranged
for selectively detecting an object (e.g. a hand) to generate a
detection result SR_1. The detection result SR_1 indicates a state
of motion of the object. The sensing device 315 comprises a sensor
array as well as related computation and/or control circuits. The
sensing device 320 is arranged for selectively detecting the object
to generate a detection result SR_2. The detection result SR_2 is
able to indicate whether the object is in a specific space L (i.e.,
a sensing covering range of the sensing system 310). The control
unit 330 is coupled to the sensing device 315 and the sensing
device 320, and is arranged for controlling operating states of the
sensing device 315 and the sensing device 320 according to the
detection results SR_1 and SR_2.
[0020] By the detection result SR_1 and the detection result SR_2,
the activation or operating states of the sensing device 315 and
the sensing device 320 can be determined. When the detection result
SR_1 indicates that the object leaves from the specific space L or
the object is motionless, the control unit 330 issues the control
command S_command1 to the sensing device 315, allowing the sensing
device 315 to enter a low power consumption operating state or stop
operating. At this time, the sensing device 315 temporarily stops
generating the detection result SR_1 to save power consumption.
More specifically, the present invention analyzes several detection
results SR_1 sampled during a period of time. Once it is found that
there is no obvious difference between these detection results SR_1
(i.e. the object is motionless) or the object leaves from the
specific space L (i.e. the detection result SR_1 indicates a sudden
change occurs and then remains unchanged), the control unit 330
will send the control command S_commandl to the sensing system 310.
By turning off/lowering down power that is supplied to a readout
circuit, a selecting circuit, a reset circuit or other circuit
components of the sensing device 315, and/or turning off a light
emitting device 312 of the sensing system 310, the power
consumption can be reduce. The light emitting device 312 is used to
illuminate the object such that the sensing device 315 is able to
detect the state of motion of the object according to changes of
lights and shadows. At the same time, the control command
S_commandl issued by the control unit 330 will be also sent to the
sensing device 320, allowing the sensing device 320 to enter a
normal operating state, generating the detection result SR_2.
Afterward, the control unit 330 determines whether to re-activate
the sensing device 315 and turn on the light emitting device 312
according to the detection result SR_2. Therefore, it can be
determined whether to allow the sensing system 310 to enter the
normal operating state.
[0021] Compared to the conventional art, the sensing device 315 of
the present invention does not intermittently activate to detect
the state of motion of the object when it enters the low power
consumption operating state. Instead, the auxiliary sensing device
320 of simple circuitry and low consumption is used to detect the
state of motion of the object. In one embodiment, the sensing
device 320 could be an ambient light sensor or a proximity sensor.
Such device cost much less power than the sensing device 315
comprised of a lot of sensing units. Although the sensing device
320 cannot recognize the gesture of the hand but it can detect
whether the object (e.g. the hand) is in the specific space L.
Since the specific space L represents the sensing covering range of
the sensing system 310, it is unnecessary to re-activate the
sensing device 315 and allow the sensing device 315 to enter the
normal operating state if the object is not in the specific space
L. Only when the object is in the specific space L, the sensing
device 315 needs to be activated.
[0022] In addition to the ambient light sensor or the proximity
sensor, it still has other different ways to realize the sensing
device 320. In one embodiment, the sensing device 320 and the
sensing device 315 could be portions of a sensor array,
respectively. Please refer to FIG. 4. A center portion of sensing
units of a sensor array 400 is arranged as the sensing device 315,
which detects the state of motion of the object according to the
changes of the shadows and the lights. The other portion of the
sensing units of the sensor array 400 is arranged as sensing device
320, which detects whether the object is in the specific space L.
Please note that the present invention is not limited in scope to
the arrangement illustrated in FIG. 4. For example, the sensing
device 320 could be one or more sensing units in any position of
the sensor array (e.g. edge, corner or center). As the number of
the sensing units that are arranged as the sensing device 320 is
smaller than the number of the sensing units that are arranged as
the sensing device 315, the power cost by the sensing device 320 is
much less than the intermittently activating the sensing device 315
to detect the state of motion of the object. Moreover, no matter
the sensing device 320 is realized by the ambient light sensor and
the proximity sensor or is realized by some of sensing units of the
sensor array, the sensing system 310 and the sensing device 320 can
be implemented with in a single chip (i.e., System on Chip, SoC),
thereby saving the size of the circuit.
[0023] When the detection result SR_2 generated by the sensing
device 320 indicates that the object enters the specific space L
again or the object begins to move, the control unit 330 issues the
control command S_Command2, allowing the sensing system 310 to
enter a normal operating state, detecting the state of motion of
the object to generate the detection result SR_1. Similarly, the
control command S_Command2 will be also issued to the sensing
device 320, ending the operation of the sensing device 320.
Operating frequencies of the sensing system 310 and the sensing
device 320 can be understood by FIG. 5.
[0024] Please refer to FIG. 6, which illustrates the relationship
between power consumption level and the control command. When the
object leaves from the specific space L or is motionless, the
control command S_Command1 is issued, causing the power consumption
level PWR_Level1 of sensing system 310 to be reduced (by allowing
the sensing device 315 to enter the low power consumption operating
state or to be de-activated, and turning off the light emitting
312), thereby stopping detecting the object. As a consequence, the
sensing device 320 is activated, entering the normal operating
state such that the power consumption level PWR_Level2 is
increased. Once the sensing device 320 indicates the lights and
shadows in the specific space L changes (i.e., the object enters
the sensing covering range again or the object begins to move), the
control command S_Command2 is issued, allowing the sensing system
310 to enter the normal operating state. At this tine, the power
consumption level PWR_Level1 of the sensing system 310 goes back to
a normal value. Also, the sensing device 320 will be de-activated
or enter the low power consumption operating state, causing the
power consumption level PWR_Level2 to be reduced.
[0025] Based on the principles mentioned above, a method of
controlling a sensing device is provided according to one
embodiment of the present invention. The method includes steps as
shown in FIG. 7. At step 700, the flow starts. At step 720, it is
determined that whether an object leaves from a specific space L or
is motionless. Such determination is accomplished by referring to a
first detection result (e.g. the detection result SR_1) generated
by a first sensing device (e.g. the sensing device 315). If it is
determined that the object does not leave from the specific space
or is not motionless, the flow goes back to step 702 to continue
determining. If it is determined that the object leaves from the
specific space or is motionless, the flow goes to step 704,
de-activating the first sensing device or allowing the first
sensing device to enter the low power consumption operating state.
At the same time, a light emitting device corresponding to the
first sensing device may be turned off. Also, a second sensing
device (e.g. the sensing device320) is activated to generate a
second detection result (e.g. the second detection result SR_2).
Afterward, the flow goes to step 706, it is determined that the
object enters the specific space L again or begins to move. If no,
the flow goes back to 706. If yes, the flow goes to step 708,
de-activating the second sensing device and activating first
sensing device to enter the normal operating state. Also, the light
emitting device is turned on such that the first sensing device is
able to detect the state of motion of the object.
[0026] Reference in the specification to "one embodiment" or "an
embodiment" means that a particular feature, structure, or
characteristic described in connection with the embodiment is
included in at least an implementation. The appearances of the
phrase "in one embodiment" in various places in the specification
are not necessarily all referring to the same embodiment. Thus,
although embodiments have been described in language specific to
structural features and/or methodological acts, it is to be
understood that claimed subject matter may not be limited to the
specific features or acts described. Rather, the specific features
and acts are disclosed as sample forms of implementing the claimed
subject matter.
[0027] In conclusion, advantages of utilizing an auxiliary sensing
device (i.e. sensing device 320) instead of intermittently
activating the gesture sensor includes shorter re-activation time
and less power consumption. This is because the auxiliary sensing
device has simple circuitry and low power consumption. Even though
the auxiliary sensing device is operated at a high frequency, the
total power consumption is still decent. Besides, if the auxiliary
sensing device is operated at the high frequency to detect, it will
not miss the state of motion of the object easily such that the
re-activated time can be shortened. As a result, the user will not
feel the delay of the re-activation.
[0028] Those skilled in the art will readily observe that numerous
modifications and alterations of the device and method may be made
while retaining the teachings of the invention. Accordingly, the
above disclosure should be construed as limited only by the metes
and bounds of the appended claims.
* * * * *